US7197875B2 - Hydraulic cylinder with coaxial, in-line reservoir - Google Patents
Hydraulic cylinder with coaxial, in-line reservoir Download PDFInfo
- Publication number
- US7197875B2 US7197875B2 US11/088,490 US8849005A US7197875B2 US 7197875 B2 US7197875 B2 US 7197875B2 US 8849005 A US8849005 A US 8849005A US 7197875 B2 US7197875 B2 US 7197875B2
- Authority
- US
- United States
- Prior art keywords
- seal
- piston
- housing
- reservoir
- pressure chamber
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Expired - Fee Related
Links
- 206010018987 Haemorrhages Diseases 0.000 abstract description 3
- 230000000740 bleeding Effects 0.000 abstract description 3
- 231100000319 bleeding Toxicity 0.000 abstract description 3
- 210000000088 Lip Anatomy 0.000 description 8
- 239000003570 air Substances 0.000 description 4
- 238000005266 casting Methods 0.000 description 2
- 238000007789 sealing Methods 0.000 description 2
- 241000083700 Ambystoma tigrinum virus Species 0.000 description 1
- 230000005540 biological transmission Effects 0.000 description 1
- 238000007906 compression Methods 0.000 description 1
- 230000000875 corresponding Effects 0.000 description 1
- 230000003247 decreasing Effects 0.000 description 1
- 230000005484 gravity Effects 0.000 description 1
- 238000003754 machining Methods 0.000 description 1
- 230000000717 retained Effects 0.000 description 1
- 239000011800 void materials Substances 0.000 description 1
- 239000011901 water Substances 0.000 description 1
Images
Classifications
-
- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F15—FLUID-PRESSURE ACTUATORS; HYDRAULICS OR PNEUMATICS IN GENERAL
- F15B—SYSTEMS ACTING BY MEANS OF FLUIDS IN GENERAL; FLUID-PRESSURE ACTUATORS, e.g. SERVOMOTORS; DETAILS OF FLUID-PRESSURE SYSTEMS, NOT OTHERWISE PROVIDED FOR
- F15B21/00—Common features of fluid actuator systems; Fluid-pressure actuator systems or details thereof, not covered by any other group of this subclass
- F15B21/04—Special measures taken in connection with the properties of the fluid
- F15B21/044—Removal or measurement of undissolved gas, e.g. de-aeration, venting or bleeding
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B60—VEHICLES IN GENERAL
- B60T—VEHICLE BRAKE CONTROL SYSTEMS OR PARTS THEREOF; BRAKE CONTROL SYSTEMS OR PARTS THEREOF, IN GENERAL; ARRANGEMENT OF BRAKING ELEMENTS ON VEHICLES IN GENERAL; PORTABLE DEVICES FOR PREVENTING UNWANTED MOVEMENT OF VEHICLES; VEHICLE MODIFICATIONS TO FACILITATE COOLING OF BRAKES
- B60T11/00—Transmitting braking action from initiating means to ultimate brake actuator without power assistance or drive or where such assistance or drive is irrelevant
- B60T11/10—Transmitting braking action from initiating means to ultimate brake actuator without power assistance or drive or where such assistance or drive is irrelevant transmitting by fluid means, e.g. hydraulic
- B60T11/16—Master control, e.g. master cylinders
- B60T11/22—Master control, e.g. master cylinders characterised by being integral with reservoir
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B62—LAND VEHICLES FOR TRAVELLING OTHERWISE THAN ON RAILS
- B62L—BRAKES SPECIALLY ADAPTED FOR CYCLES
- B62L3/00—Brake-actuating mechanisms; Arrangements thereof
- B62L3/02—Brake-actuating mechanisms; Arrangements thereof for control by a hand lever
- B62L3/023—Brake-actuating mechanisms; Arrangements thereof for control by a hand lever acting on fluid pressure systems
-
- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F15—FLUID-PRESSURE ACTUATORS; HYDRAULICS OR PNEUMATICS IN GENERAL
- F15B—SYSTEMS ACTING BY MEANS OF FLUIDS IN GENERAL; FLUID-PRESSURE ACTUATORS, e.g. SERVOMOTORS; DETAILS OF FLUID-PRESSURE SYSTEMS, NOT OTHERWISE PROVIDED FOR
- F15B7/00—Systems in which the movement produced is definitely related to the output of a volumetric pump; Telemotors
- F15B7/06—Details
- F15B7/08—Input units; Master units
-
- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F15—FLUID-PRESSURE ACTUATORS; HYDRAULICS OR PNEUMATICS IN GENERAL
- F15B—SYSTEMS ACTING BY MEANS OF FLUIDS IN GENERAL; FLUID-PRESSURE ACTUATORS, e.g. SERVOMOTORS; DETAILS OF FLUID-PRESSURE SYSTEMS, NOT OTHERWISE PROVIDED FOR
- F15B7/00—Systems in which the movement produced is definitely related to the output of a volumetric pump; Telemotors
- F15B7/06—Details
- F15B7/10—Compensation of the liquid content in a system
Abstract
Description
The present invention relates to the field of hydraulic devices and more particularly to hydraulic cylinders.
Hydraulic cylinders have a long history of use in regard to automobile and truck applications for actuation of brakes and clutches. Applications for hydraulic cylinders in motorcycles for actuating brakes and clutches are becoming more common, particularly in conjunction with the actuation of disk brakes.
One problem encountered in the use of prior art hydraulic cylinders particularly for motorcycles and other vehicles and equipment with hand-operated controls is the providing of a hydraulic fluid reservoir for the master cylinder. One approach in the field of motorcycles has been to mount a reservoir on the handlebars of the motorcycle and connect the reservoir to the hand-lever-operated hydraulic cylinder using a hydraulic line. This has not been completely satisfactory owing to the increase in the number of parts and the attendant increase in cost and maintenance requirements, the cluttering of the handlebar area and so forth. Annular reservoirs that surround the hydraulic cylinder likewise have been provided, but are less than satisfactory owing to their bulk.
In one aspect, the present hydraulic device comprises a hydraulic cylinder with a coaxial reservoir in line with the pressure chamber of the pressure cylinder.
As shown in
It should be noted that, while the foregoing discussion has related to a brake lever, any of a number of different means may be used to actuate the hydraulic cylinder 24, and the hydraulic cylinder may be used to actuate any number of devices, such as a clutch, transmission, throttle, and so forth. Further, hydraulic cylinders according to the present invention may be used in applications other than motorcycles, such as in snowmobiles, jet skis, boats, farm and lawn equipment, ATV's, stationary equipment and the like.
Referring to
The volume of space between the cups 30, 32 comprises the reservoir 42. The shaft 44 of the piston 28 extends through the reservoir 42, and the cup 32, which is the second seal member, is free to slide along the shaft 44 of the piston 28 in response to changes in the volume of hydraulic fluid in the reservoir 42 and provides a seal both between itself and the shaft and between itself and the bore of the housing 26. The pressure chamber 40 and reservoir 42 are thus coaxial and mounted in line with one another in the hydraulic cylinder of the present embodiment. The diameter of the shaft 44 may be reduced or enlarged to alter the volume of the reservoir 42. In such case, of course, a cup 32 or other sealing member with an inside diameter corresponding to the diameter of the shaft 44 would have to be used. Similarly, the bore of the cylinder body 26 could be enlarged to provide additional reservoir capacity, and in such case, a cup 32 or other sealing member having an appropriately enlarged outside diameter could be used. In the context of a hydraulic braking system, the volume of fluid required by the hydraulic cylinder that actually operates the brake may increase as the brake pads wear. To account for such additional demands for fluid from the reservoir 42, the volume of the reservoir 42 may be chosen as at least twice the volume of the pressure chamber.
As mentioned above, the spring 34 acts between the forward end 36 of the piston 28 and the forward end 38 of the cylinder body 26. This biases the piston 28 toward the open end 46 of the cylinder body 26. An annulus 48 is mounted on the shaft 44 adjacent the distal end of the shaft 44 and is maintained in contact with a shoulder 50 on the shaft by a retaining ring 52 that is mounted in a groove on the shaft 44. Travel of the piston 28 away from the forward end of the cylinder body 26 is restricted by a retaining ring 54 mounted in a groove in the cylinder body 26. This retaining ring 54 is positioned to engage the annulus 48 that, in turn, is engaged with the shoulder 50 on the shaft 44 of the piston 28. The retaining ring 54 thus functions as a stop to limit movement of the piston 28 away from the outlet. An aperture 56 is provided in the annulus 48 to allow a wire or other probe 66 to be extended into the space between the annulus 48 and the cup 32. A socket 58 is provided in the end of the shaft 44 of the piston. The distal end of the push rod 22 may be inserted into the socket such that moving the brake lever 10 from the extended position 16 to the retracted position 20 causes the piston 26 to be moved toward the forward end 38 of the cylinder body, compressing the spring 34 and forcing hydraulic fluid from the pressure chamber 40 through the outlet 41. The socket 58 serves as the force receiver in the present embodiment. In other embodiments, the force may be applied to the shaft through a ball-in-socket joint, a clevis and pin arrangement or in other such manners.
A first channel 60 is formed into the inner wall of the cylinder body 26. As shown in
Referring next to
In an alternate embodiment, as shown in
A channel 86 is formed in the exterior of the insert 82, as by turning down that portion of the insert 82 on a lathe or milling or otherwise forming the insert, and holes 88, 90 are drilled or otherwise formed in the insert 82 so that the pressure chamber 40 and reservoir 42 communicate with one another through the channel 86 when the lip 62 of the cup 30 is positioned longitudinally in the interior of the insert 82 such that it is between the two holes 88, 90.
Rather than using a second hydraulic cup such as the cup 32 of
A drain channel 98 is machined or otherwise formed in the exterior of the cylindrical insert 82, and a hole or holes 100 are drilled or otherwise formed such that they extend from the drain channel 98 into the interior of the cylindrical insert 82. When the annular mount 92 is positioned sufficiently proximate to the annulus 48, the reservoir 42 can communicate with the drain channel 98 through the hole or holes 100, for example, for bleeding air or hydraulic fluid out of the reservoir 42.
A threaded hole 102 may be provided in the housing 84 in a position such that it communicates with the drain channel. A bleed plug 104 may be screwed into the hole 102. Bleeding of hydraulic fluid may be facilitated by a bleed tube 106 attached to the bleed plug 104.
In use, when a force is applied to the shaft 44, as through the socket 58, the piston 28 moves from a position remote from the outlet 41 (see, e.g.,
After the lip 62 of the cup 30 has moved past the channel 60, the reservoir 42 is sealed from the pressure chamber 40 by the cup 30. As such, the hydraulic fluid in the pressure chamber 40 is thereafter forced through the outlet 41 as the piston 28 and cup 30 move toward the forward end of the cylinder body.
Upon release of the force applied to the piston 28 through the shaft 44, the spring 34 urges the piston 28 away from the front end of the cylinder body, and hydraulic fluid returns to the pressure chamber through the outlet 41. When the lip 62 of the cup 30 is no longer forward of the channel 60, hydraulic fluid can flow from the reservoir 44 into the pressure chamber 40. If the hydraulic cylinder (not shown) operated by the hydraulic cylinder 24 requires additional fluid, as may be occasioned by wear of brake pads in the event that the hydraulic cylinder is used to actuate a hydraulic brake mechanism, additional hydraulic fluid may flow from the reservoir into the pressure chamber 40 when the cup 30 is positioned such that the channel 60 communicates freely with both the reservoir 42 and pressure chamber 40. This may cause the follower cup 32 to move along the shaft 44 of the piston 28 toward the cup 30, decreasing the volume of the reservoir 42.
Ultimately, movement of the piston 28 away from the forward end 38 of the cylinder body 26 is limited by the retaining ring 54 that prevents further movement of the annulus 48, and hence the piston 28, out of the distal end of the cylinder body 26.
Fluid may flow through the channel 64 when the lip of the cup 32 has moved past the front end of the channel 64. Referring to
It will be appreciated by those skilled in the art that the coaxial, in-line design of the hydraulic cylinders 24, 80 of the embodiments of the invention do not rely on gravity feed. Further, the cup 32 and follower 92 as shown, for example, in
Although the present invention has been described in considerable detail with reference to certain preferred embodiments, other embodiments are possible. Therefore, the spirit or scope of the appended claims should not be limited to the description of the embodiments contained herein.
Claims (12)
Priority Applications (1)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
US11/088,490 US7197875B2 (en) | 2005-03-24 | 2005-03-24 | Hydraulic cylinder with coaxial, in-line reservoir |
Applications Claiming Priority (1)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
US11/088,490 US7197875B2 (en) | 2005-03-24 | 2005-03-24 | Hydraulic cylinder with coaxial, in-line reservoir |
Publications (2)
Publication Number | Publication Date |
---|---|
US20060213192A1 US20060213192A1 (en) | 2006-09-28 |
US7197875B2 true US7197875B2 (en) | 2007-04-03 |
Family
ID=37033816
Family Applications (1)
Application Number | Title | Priority Date | Filing Date |
---|---|---|---|
US11/088,490 Expired - Fee Related US7197875B2 (en) | 2005-03-24 | 2005-03-24 | Hydraulic cylinder with coaxial, in-line reservoir |
Country Status (1)
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US (1) | US7197875B2 (en) |
Cited By (6)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US20080314712A1 (en) * | 2005-12-22 | 2008-12-25 | Frank Cherubin | Actuating Armature |
US20090152063A1 (en) * | 2007-12-13 | 2009-06-18 | Szu-Fang Tsai | Pumping device for a hydraulic brake of a bicycle |
US20100052415A1 (en) * | 2007-01-31 | 2010-03-04 | Giancarlo Vezzoli | Hydraulic pump |
US20110162929A1 (en) * | 2010-01-06 | 2011-07-07 | Ashima Ltd. | Hydraulic brake system |
US10189539B2 (en) | 2013-01-18 | 2019-01-29 | Gustav Magenwirth Gmbh & Co. Kg | Master cylinder device for a hydraulic disk brake |
US20190039679A1 (en) * | 2017-08-03 | 2019-02-07 | Shimano Inc. | Operating device |
Families Citing this family (4)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US8561402B2 (en) | 2007-06-11 | 2013-10-22 | Sram, Llc | Master cylinder for a hydraulic actuation system for a handlebar-steered vehicle |
US7757488B2 (en) * | 2007-06-11 | 2010-07-20 | Sram, Llc | Master cylinder assembly for a hydraulic actuation system for a handlebar-steered vehicle |
US8046996B2 (en) * | 2007-06-11 | 2011-11-01 | Sram, Llc | Master cylinder assembly for a hydraulic actuation system for a handlebar-steered vehicle |
WO2012113349A1 (en) * | 2011-02-25 | 2012-08-30 | Innozeal Technology Ltd. | Hydraulic cylinder and spool type hydraulic control valve with metallic seal ring |
Citations (16)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US1963114A (en) | 1929-04-12 | 1934-06-19 | Hydraulic Brake Co | Hydraulic brake mechanism |
US2239673A (en) | 1938-06-06 | 1941-04-29 | Hydraulic Brake Co | Fluid pressure braking system |
US2268624A (en) * | 1940-03-26 | 1942-01-06 | Ernest I Schwarz | Packing cup for brake mechanism |
US2500502A (en) * | 1946-01-12 | 1950-03-14 | Wingfoot Corp | Master cylinder |
US3338337A (en) | 1965-12-15 | 1967-08-29 | Elmer E Freeland | Hydraulic cycle brake |
US3473330A (en) * | 1966-11-05 | 1969-10-21 | Teves Gmbh Alfred | Master cylinder for brake systems and the like |
US3899057A (en) | 1972-01-25 | 1975-08-12 | Dba Sa | Hydraulic control circuit |
US4566277A (en) * | 1981-05-21 | 1986-01-28 | Itt Industries, Inc. | Pressurized fluid supplying arrangement particularly a master cylinder of a clutch |
US4679680A (en) * | 1983-11-07 | 1987-07-14 | Lucas Industries Public Limited Company | Clutch master cylinder with internal reservoir |
US4823677A (en) | 1988-01-19 | 1989-04-25 | General Electric Company | Brake power assist servomotor |
US4921081A (en) | 1988-12-22 | 1990-05-01 | Autra-Bike Co., Inc. | Hydraulic brake apparatus for bicycles |
US4924673A (en) | 1988-02-17 | 1990-05-15 | Automotive Products Plc | Master cylinder with parallel-bore reservoir |
US5477682A (en) | 1992-01-27 | 1995-12-26 | Automotive Products France, Sa | Hydraulic master cylinder and reservoir assembly |
US6336525B1 (en) | 2000-06-19 | 2002-01-08 | Tony Leng | Disc brake oil pressure adjusting device for bikes |
US6370877B1 (en) | 2001-01-30 | 2002-04-16 | Chang Hui Lin | Brake handle device for hydraulic brake assembly |
US6502675B1 (en) | 2000-01-11 | 2003-01-07 | Frank G. Andrus | Integrated handlebar and master cylinder having piston and hydraulic line coaxially aligned with major central axis of handlebar |
-
2005
- 2005-03-24 US US11/088,490 patent/US7197875B2/en not_active Expired - Fee Related
Patent Citations (16)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US1963114A (en) | 1929-04-12 | 1934-06-19 | Hydraulic Brake Co | Hydraulic brake mechanism |
US2239673A (en) | 1938-06-06 | 1941-04-29 | Hydraulic Brake Co | Fluid pressure braking system |
US2268624A (en) * | 1940-03-26 | 1942-01-06 | Ernest I Schwarz | Packing cup for brake mechanism |
US2500502A (en) * | 1946-01-12 | 1950-03-14 | Wingfoot Corp | Master cylinder |
US3338337A (en) | 1965-12-15 | 1967-08-29 | Elmer E Freeland | Hydraulic cycle brake |
US3473330A (en) * | 1966-11-05 | 1969-10-21 | Teves Gmbh Alfred | Master cylinder for brake systems and the like |
US3899057A (en) | 1972-01-25 | 1975-08-12 | Dba Sa | Hydraulic control circuit |
US4566277A (en) * | 1981-05-21 | 1986-01-28 | Itt Industries, Inc. | Pressurized fluid supplying arrangement particularly a master cylinder of a clutch |
US4679680A (en) * | 1983-11-07 | 1987-07-14 | Lucas Industries Public Limited Company | Clutch master cylinder with internal reservoir |
US4823677A (en) | 1988-01-19 | 1989-04-25 | General Electric Company | Brake power assist servomotor |
US4924673A (en) | 1988-02-17 | 1990-05-15 | Automotive Products Plc | Master cylinder with parallel-bore reservoir |
US4921081A (en) | 1988-12-22 | 1990-05-01 | Autra-Bike Co., Inc. | Hydraulic brake apparatus for bicycles |
US5477682A (en) | 1992-01-27 | 1995-12-26 | Automotive Products France, Sa | Hydraulic master cylinder and reservoir assembly |
US6502675B1 (en) | 2000-01-11 | 2003-01-07 | Frank G. Andrus | Integrated handlebar and master cylinder having piston and hydraulic line coaxially aligned with major central axis of handlebar |
US6336525B1 (en) | 2000-06-19 | 2002-01-08 | Tony Leng | Disc brake oil pressure adjusting device for bikes |
US6370877B1 (en) | 2001-01-30 | 2002-04-16 | Chang Hui Lin | Brake handle device for hydraulic brake assembly |
Cited By (11)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US20080314712A1 (en) * | 2005-12-22 | 2008-12-25 | Frank Cherubin | Actuating Armature |
US8621861B2 (en) | 2005-12-22 | 2014-01-07 | Gustav Magenwirth Gmbh & Co. Kg | Actuating armature |
US9387904B2 (en) * | 2007-01-31 | 2016-07-12 | Formula S.A.S. Di “Formula Group S.R.L.” & C. | Hydraulic pump |
US20100052415A1 (en) * | 2007-01-31 | 2010-03-04 | Giancarlo Vezzoli | Hydraulic pump |
US8764125B2 (en) * | 2007-01-31 | 2014-07-01 | Formula S.R.L. | Hydraulic pump |
US20140360829A1 (en) * | 2007-01-31 | 2014-12-11 | Formula S.R.L. | Hydraulic pump |
US20090152063A1 (en) * | 2007-12-13 | 2009-06-18 | Szu-Fang Tsai | Pumping device for a hydraulic brake of a bicycle |
US20110162929A1 (en) * | 2010-01-06 | 2011-07-07 | Ashima Ltd. | Hydraulic brake system |
US10189539B2 (en) | 2013-01-18 | 2019-01-29 | Gustav Magenwirth Gmbh & Co. Kg | Master cylinder device for a hydraulic disk brake |
US20190039679A1 (en) * | 2017-08-03 | 2019-02-07 | Shimano Inc. | Operating device |
US10526038B2 (en) * | 2017-08-03 | 2020-01-07 | Shimano Inc. | Operating device |
Also Published As
Publication number | Publication date |
---|---|
US20060213192A1 (en) | 2006-09-28 |
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